©,　2014,　Shanghai　Power　Equipment　Research　Institute.　All　right　reserved.　The　effect　of　temperature　on　SO2/SO3　conversion　rate　under　the　action　of　SCR　catalyst　was　studied　on　a　self-developed　experimental　setup,　in　which　case,　the　absorption　capability　of　Ca-based　and　Mg-based　sorbents　to　SO3　was　investigated,　and　simultaneously　the　samples　were　analyzed　using　scanning　electron　microscopy　before　and　after　adsorption　experiment,　so　as　to　analyze　the　factors　influencing　the　SO3　adsorption　by　Ca-based　and　Mg-based　sorbents　and　the　removal　mechanism.　Results　show　that　the　SO2/SO3　conversion　rate　increases　with　rising　reaction　temperature,　and　the　increasing　tendency　slows　down　when　the　temperature　gets　up　to　300℃.　The　conversion　rate　has　a　good　linear　relationship　with　the　temperature　in　the　reaction　scope.　The　adsorption　capability　of　the　four　sorbents　tested　to　SO3　are　ranked　from　high　to　low　as　follows:　Mg(OH)2,　Ca(OH)2,　MgO　and　CaO.